The present disclosure relates to heater control, and in particular to the control of multiple heaters via pulse width modulation.
Heaters are often used to heat fluids (e.g., air, liquids, etc.) to a target temperature. For example, in aircraft environmental control systems, a heater can be disposed within an airflow duct (e.g., an airflow duct of a galley heating system) to heat air passing through the duct to a zone of the aircraft. Often, a thermostat or other such controller receives a target temperature (e.g., via user input) and controls operation of the heater to achieve the target temperature based on feedback from a temperature sensor that measures a temperature of the air within the zone or duct. In some cases, such as in the case of a flow duct, a space within which the heater device is disposed can be limited. For instance, a heater disposed within a flow duct can encompass all or part of the available dimensions within which the heater can be installed. In such cases, it can be difficult to increase an amount of available heat to a system serviced by the heater because an increase in power output of a heater device is often accompanied by an increase in the size of the heater. Accordingly, it can be difficult to increase the amount of available heat without redesigning (e.g., enlarging) the flow duct within which the heater is installed. Such redesigns can be expensive and impractical to implement.